The invention relates to novel substituted phenyluracils, to processes for their preparation, to novel intermediates and to their use as herbicides.
It is known that certain substituted uracils have herbicidal properties (cf. EP 408382/U.S. Pat. No. 5,084,084/U.S. Pat. No. 5,127,935/U.S. Pat. No. 5,154,755, EP 5,63,384, EP 648749, WO 91/00278, U.S. Pat. No. 4,979,982, U.S. Pat. No. 5,169,430, DE 4329537). However, these compounds have hitherto not attained any major importance.
This invention, accordingly, provides the novel substituted phenyluracils of the general formula (I) 
in which
R1 represents hydrogen, halogen or optionally substituted alkyl,
R2 represents optionally substituted alkyl,
R3 represents hydrogen, amino or respectively optionally substituted alkyl, alkenyl or alkinyl,
R4 represents hydrogen, cyano or halogen,
R5 represents cyano or thiocarbamoyl, and
R6 represents one of the groupings below
xe2x80x94C(R7,R8)xe2x80x94C(R7,R8)xe2x80x94R9 or xe2x80x94C(R7)xe2x95x90C(R8)xe2x80x94R9 
xe2x80x83in which
R7 and R8 are identical or different and each represents independently of the other hydrogen, hydroxyl, mercapto, halogen or respectively optionally substituted alkyl, alkoxy or alkylthio, and
R9 represents cyano, formyl, alkylcarbonyl, the grouping xe2x80x94COxe2x80x94OR10 or the grouping xe2x80x94COxe2x80x94N(R11,R12), where
R10 represents hydrogen or represents a respectively optionally substituted radical from the group consisting of alkyl, alkenyl, alkinyl, cycloalkyl, cycloalkylalkyl, aryl, arylalkyl, heterocyclyl and heterocyclylalkyl,
R11 represents hydrogen or represents a respectively optionally substituted radical from the group consisting of alkyl, alkoxy, alkenyl and alkinyl, and
R12 represents hydrogen or represents a respectively optionally substituted radical from the group consisting of alkyl, alkenyl, alkinyl, cycloalkyl, cycloalkylalkyl, aryl, arylalkyl, heterocyclyl and heterocyclylalkyl, or together with R11 represents alkanediyl.
The novel substituted phenyluracils of the general formula (I) are obtained when
(a) aminophenyluracils of the general formula (II) 
in which
R1, R2, R3, R4 and R5 are each as defined above,
or acid adducts of compounds of the formula (II)
are reacted with an alkali metal nitrite or alkyl nitrite and with a hydrogen halide (HX1) or a metal halide (MX1), if appropriate in the presence of a diluent, and the resulting diazonium salts of the general formula (III) 
in which
R1, R2, R3, R4 and R5 are each as defined above and
X1 represents halogen,
are reacted with acrylic acid derivatives of the general formula (IV)
C(R7R8)xe2x95x90C(R7)xe2x80x94R9xe2x80x83xe2x80x83(IV) 
in which
R7, R8 and R9 are each as defined above,
in the presence of hydrogen halides (HX1), if appropriate in the presence of catalysts, if appropriate in the presence of water and if appropriate in the presence of the organic solvent employed initially, or
(b) substituted phenyluracils of the general formula (Ia) 
in which
R1, R2, R3, R4, R5, R7, R8 and R9 are each as defined above,
but where at least one of the radicals R7/R8 represents hydrogen and at least one further radical R7/R8 in a position vicinal to the first represents halogen
are reacted with an acid acceptor, if appropriate in the presence of a diluent.
It is also possible to convert the compounds of the general formula (I) into other compounds of the general formula (I) according to the above definition using other conventional methods, for example by amination or alkylation (e.g. R3: Hxe2x86x92NH2, Hxe2x86x92CH3), reaction with hydrogen sulphide (e.g. R5: CNxe2x86x92CSNH2), nucleophilic substitution (e.g. R8: Clxe2x86x92SCH3), if appropriate addition of hydrogen, halogen or hydrogen halide to a Cxe2x80x94C double bond (cf. definition of R6), hydrolysis (e.g. R9: CNxe2x86x92COOH).
If the compounds of the formula (I) according to the invention contain olefinic double bonds (cf. definition of R6), the invention relates both to the individual E and Z or cis and trans isomers separable by conventional methods, and also to any mixtures of these isomers.
The novel substituted phenyluracils of the general formula (I) have strong herbicidal activity.
In the definitions, the saturated or unsaturated hydrocarbon chains, such as alkyl, alkenyl or alkinyl, are in each case straight-chain or branched.
Halogen generally represents fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine, in particular fluorine or chlorine.
The invention preferably provides compounds of the formula (I) in which
R1 represents hydrogen, fluorine, chlorine, bromine or optionally fluorine- and/or chlorine-substituted C1-C4-alkyl,
R2 represents optionally fluorine- and/or chlorine-substituted C1-C4-alkyl,
R3 represents hydrogen, amino, represents optionally cyano-, fluorine-, chlorine- or C1-C4-alkoxy-substituted C1-C6-alkyl or represents optionally fluorine- and/or chlorine-substituted C2-C6-alkenyl or C2-C6-alkinyl,
R4 represents hydrogen, cyano, fluorine or chlorine,
R5 represents cyano or thiocarbamoyl, and
R6 represents one of the groupings below
xe2x80x94C(R7,R8)xe2x80x94C(R7,R8)xe2x80x94R9 or xe2x80x94C(R7)xe2x95x90C(R8)xe2x80x94R9 
xe2x80x83in which
R7 and R8 are identical or different and each represents independently of the other hydrogen, hydroxyl, mercapto, fluorine, chlorine, bromine or respectively optionally cyano-, fluorine-, chlorine- or C1-C4-alkoxy-substituted C1-C4-alkyl, C1-C4-alkoxy or C1-C4-alkylthio, and
R9 represents cyano, formyl, C1-C4-alkyl-carbonyl, the grouping xe2x80x94COxe2x80x94OR10 or the grouping xe2x80x94COxe2x80x94N(R11,R12), where
R10 represents hydrogen or represents optionally cyano-, fluorine-, chlorine- or C1-C4-alkoxy-substituted C1-C10-alkyl,
R10 furthermore represents respectively optionally fluorine-, chlorine- or bromine-substituted C3-C10-alkenyl or C3-C10-alkinyl,
R10 furthermore represents respectively optionally cyano-, fluorine-, chlorine-, bromine-, C1-C4-alkyl- or C1-C4-alkoxy-carbonyl-substituted C3-C6-cycloalkyl or C3-C6-cycloalkyl-C1-C4-alkyl,
R10 furthermore represents respectively optionally cyano-, fluorine-, chlorine-, bromine-, C1-C4-alkyl-, C1-C4-halogenoalkyl-, C1-C4-alkoxy-, C1-C4-halogenoalkoxy-, C1-C4-alkylthio-, C1-C4-halogenoalkylthio- or C1-C4-alkoxy-carbonyl-substituted phenyl, phenyl- C1-C4-alkyl, furyl, furylmethyl, tetrahydrofuryl, tetrahydrofurylmethyl, thienyl, thienylmethyl, tetrahydrothienyl, tetrahydrothienylmethyl, perhydropyranyl, perhydropyranylmethyl, oxazolyl, oxaazolylmethyl, thiazolyl, thiazolylmethyl, oxadiazolyl, oxadiazolylmethyl, thiadiazolyl, thiadiazolylmethyl, dioxolanyl, dioxolanylmethyl, pyridinyl, pyridinylmethyl, pyrimidinyl or pyrimidinylmethyl,
R11 represents hydrogen or represents respectively optionally cyano-, fluorine-, chlorine- or C1-C4-alkoxy-substituted C1-C6-alkyl or C1-C6-alkoxy,
R11 furthermore represents respectively optionally fluorine-, chlorine- or bromine-substituted C3-C6-alkenyl or C3-C6-alkinyl, and
R12 represents hydrogen or represents optionally cyano-, fluorine-, chlorine- or C1-C4-alkoxy-substituted C1-C10-alkyl,
R12 furthermore represents respectively optionally fluorine-, chlorine- or bromine-substituted C3-C10-alkenyl or C3-C10-alkinyl,
R12 furthermore represents respectively optionally cyano-, fluorine-, chlorine-, bromine-, C1-C4-alkyl- or C1-C4-alkoxy-carbonyl-substituted C3-C6-cycloalkyl or C3-C6-cycloalkyl-C1-C4-alkyl,
R12 furthermore represents respectively optionally cyano-, fluorine-, chlorine-, bromine-, C1-C4-alkyl-, C1-C4-halogenoalkyl-, C1-C4-alkoxy-, C1-C4-halogenoalkoxy-, C1-C4-alkylthio-, C1-C4-halogenoalkylthio- or C1-C4-alkoxy-carbonyl-substituted phenyl, phenyl-C1-C4-alkyl, furyl, furylmethyl, tetrahydrofuryl, tetrahydrofurylmethyl, thienyl, thienylmethyl, tetrahydrothienyl, tetrahydrothienylmethyl, perhydropyranyl, perhydropyranylmethyl, oxazolyl, oxadiazolylmethyl, thiazolyl, thiazolylmethyl, oxadiazolyl, oxadiazolylmethyl, thiadiazolyl, thiadiazolylmethyl, dioxolanyl, dioxolanylmethyl, pyridinyl, pyridinylmethyl, pyrimidinyl or pyrimidinylmethyl or together with R11 represents C2-C6-alkanediyl.
The invention in particular provides compounds of the formula (I) in which
R1 represents hydrogen, fluorine, chlorine, bromine or optionally fluorine- and/or chlorine-substituted methyl or ethyl,
R2 represents optionally fluorine- and/or chlorine-substituted methyl or ethyl,
R3 represents hydrogen, amino, represents optionally cyano-, fluorine-, chlorine-, methoxy- or ethoxy-substituted methyl, ethyl, n- or i-propyl, n-, i-, s- or t-butyl, or represents optionally fluorine- and/or chlorine-substituted propenyl, butenyl, propinyl or butinyl,
R4 represents hydrogen, fluorine or chlorine,
R5 represents cyano or thiocarbamoyl, and
R6 represents one of the groupings below
xe2x80x94C(R7,R8)xe2x80x94C(R7,R8)xe2x80x94R9 or xe2x80x94C(R7)xe2x95x90C(R8)xe2x80x94R9 
xe2x80x83in which
R7 and R8 are identical or different and each represents independently of the other hydrogen, fluorine, chlorine, bromine or respectively optionally cyano-, fluorine-, chlorine-, methoxy- or ethoxy-substituted methyl, ethyl, methoxy, ethoxy, methylthio or ethylthio, and
R9 represents cyano, the grouping xe2x80x94COxe2x80x94OR10 or the grouping xe2x80x94COxe2x80x94N(R11,R12), where
R10 represents hydrogen or represents respectively optionally cyano-, fluorine-, chlorine-, methoxy- or ethoxy-substituted methyl, ethyl, n- or i-propyl, n-, i-, s- or t-butyl, n-, i-, s- or t-pentyl,
R10 furthermore represents respectively optionally fluorine-, chlorine- or bromine-substituted propenyl, butenyl, pentenyl, propinyl, butinyl or pentinyl,
R10 furthermore represents respectively optionally cyano-, fluorine-, chlorine-, bromine-, methyl-, ethyl-, methoxycarbonyl- or ethoxycarbonyl-substituted cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, cyclobutylmethyl, cyclopentylmethyl or cyclohexylmethyl,
R10 furthermore represents respectively optionally cyano-, fluorine-, chlorine-, bromine-, methyl-, ethyl-, trifluoromethyl-, methoxy-, ethoxy-, difluoromethoxy-, trifluoromethoxy-, methylthio-, ethylthio-, difluoromethylthio-, trifluoromethyl-, methoxycarbonylor ethoxycarbonyl-substituted phenyl, phenylmethyl, phenylethyl, furyl, furylmethyl, tetrahydrofuryl, tetrahydrofurylmethyl, thienyl, thienylmethyl, tetrahydrothienyl, tetrahydrothienylmethyl, perhydropyranyl, perhydropyranylmethyl, oxazolyl, oxazolylmethyl, thiazolyl, thiazolylmethyl, oxadiazolyl, oxadiazolylmethyl, thiadiazolyl, thiadiazolylmethyl, dioxolanyl, dioxolanylmethyl, pyridinyl, pyridinylmethyl, pyrimidinyl or pyrimidinylmethyl,
R11 represents hydrogen or represents respectively optionally cyano-, fluorine-, chlorine-, methoxy- or ethoxy-substituted methyl, ethyl, methoxy or ethoxy,
R11 furthermore represents respectively optionally fluorine-, chlorine- or bromine-substituted propenyl or propinyl, and
R12 represents hydrogen or represents optionally cyano-, fluorine-, chlorine-, methoxy- or ethoxy-substituted methyl, ethyl, n- or i- propyl, n-, i-, s- or t-butyl, n-, i-, s- or t-pentyl,
R12 furthermore represents respectively optionally fluorine-, chlorine- or bromine-substituted propenyl, butenyl, pentenyl, propinyl, butinyl or pentinyl, represents respectively optionally cyano-, fluorine-, chlorine-, bromine-, methyl-, ethyl-, methoxycarbonyl- or ethoxycarbonyl- substituted cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, cyclo-butylmethyl, cyclopentylmethyl or cyclohexylmethyl,
R12 furthermore represents respectively optionally cyano-, fluorine-, chlorine-, bromine-, methyl-, ethyl-, trifluoromethyl-, methoxy-, ethoxy-, difluoromethoxy-, trifluoromethoxy-, methylthio-, ethylthio-, difluoromethylthio-, trifluoromethylthio-, methoxycarbonyl- or ethoxycarbonyl-substituted phenyl, phenylmethyl, phenylethyl, furyl, furylmethyl, tetrahydrofuryl, tetrahydrofurylmethyl, thienyl, thienylmethyl, tetrahydrothienyl, tetrahydrothienylmethyl, perhydro-pyranyl, perhydropyranylmethyl, oxazolyl, oxazolylmethyl, thiazolyl, thiazolylmethyl, oxadiazolyl, oxadiazolylmethyl, thiadiazolyl, thiadiazolylmethyl, dioxolanyl, dioxolanylmethyl, pyridinyl, pyridinylmethyl, pyrimidinyl or pyrimidinylmethyl.
The general or preferred radical definitions listed above are valid both for the end products of the formula (I) and, in a corresponding manner, also for the starting materials or intermediates which are required in each case for the preparation. These radical definitions can be combined with each other at will, i.e. combinations between the given preferred ranges are also possible.